CN103664296B - Method for regulating nutrients in diammonium phosphate product - Google Patents
Method for regulating nutrients in diammonium phosphate product Download PDFInfo
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- CN103664296B CN103664296B CN201310684365.6A CN201310684365A CN103664296B CN 103664296 B CN103664296 B CN 103664296B CN 201310684365 A CN201310684365 A CN 201310684365A CN 103664296 B CN103664296 B CN 103664296B
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Abstract
The invention discloses a method for regulating nutrients in a diammonium phosphate product. Aiming at the characteristic that the danger coefficient for regulating the nutrient ratio in the diammonium phosphate product by adding concentrated sulfuric acid is high, ammonium sulphate slurry and ammonium sulfate crystal are produced through adding and dissolving phosphogypsum into diammonium phosphate slurry so as to embed ammonium sulfate into the diammonium phosphate product, thus the stable product quality is maintained, the consumption of a phosphorus resource is reduced, the nitrogen content of the diammonium phosphate product is increased and the production cost is lowered. The ammonium sulfate (NH4) 2SO4 has the nitrogen content of 21%; after the ammonium sulfate is added into the diammonium phosphate product, components of the diammonium phosphate product can be changed and the ammonia content of the diammonium phosphate product can be increased; by the method, not only phosphorus reduction and nitrogen increase of the diammonium phosphate product can be effectively promoted to keep stable product quality; the used ammonium sulfate slurry is produced by a device for producing ammonium dihydrogen phosphate from the phosphogypsum, so that high consumption of the phosphogypsum can save the treatment cost of the phosphogypsum, reduce the environment-protecting pressure and prolong the service life of a phosphogypsum slag field.
Description
Technical field
The present invention relates to diammonium phosphate, particularly relate to the method that in features of DAP production process, product nutrient regulates.
Technical background
Diammonium phosphate is water-soluble high-efficient composite fertilizers nitrogenous, two kinds of nutritive ingredients of phosphorus, and it produces main Traditional Method or the slurry process of adopting.It is raw material that Traditional Method technique be take wet method strong phosphoric acid and the high-purity liquefied ammonia that concentration is 45%～48%, adopts pre-neutralization, tubular reactor to prepare phosphor ammonium slurry, and in drum ammoniation granulating machine, coating granulation forms.
The main evaluation index of quality of diammonium phosphate product comprises available phosphorus (P
2o
5), total nitrogen content, water-soluble etc.Traditional Method granular diammonium phosphate premium grads nutrient (nitrogen phosphorus potassium) specification is 18-46-0.The diammonium phosphate product that strong phosphoric acid with 45.0%～48.0% is produced, available phosphorus content generally can reach 46.0%, but keep nitrogen content to reach 18%, has certain difficulty.In process of production, for preparing to press the nutrients ratio of 18:46:0, need to add certain sulfuric acid or filler and enter in slip formula, promote diammonium phosphate product to fall phosphorus and carry nitrogen.But sulfuric acid has strong corrodibility, strong oxidizing property, dehydration property etc., very exothermic in slip system, adding procedure danger coefficient is higher.
Seriously superfluous in the face of diammonium phosphate production capacity, market is tending towards saturated situation, and in the face of fierce market competition, most of enterprise is to improve product performance, stabilized product quality, to reduce production costs and seek living space.Optimizing product quality, reduces production costs and need to set about from production process technology.Phosphate rock resource is that phosphoric acid compound fertilizer is produced one of topmost resource, as product available phosphorus (P
2o
5) content is when higher, significantly promotes features of DAP production cost, causes product nutrient to depart from 18:46:0 ratio simultaneously.Keeping product nutrient available phosphorus to meet under the prerequisite of GB>=46.00%, by product available phosphorus (P
2o
5) content by actual value 47% while dropping to 46%, for a large-scale phosphoric acid phosphorus compound fertilizer manufacturing enterprise that produces 900000 tons/year per year, can save 9000 tons/year of Vanadium Pentoxide in FLAKESs.
Summary of the invention
The object of the invention is, for adding the high feature of vitriol oil regulating nutrients of diammonium phosphate product ratio danger coefficient, provides a kind of to the method in features of DAP production process, product nutrient being regulated.
The method that nutrients of diammonium phosphate product of the present invention regulates, by employing, add phosphogypsum ammonium sulfate slurry processed and ammonia sulfate crystal, make an addition in the slip of diammonium phosphate and dissolve, ammonium sulfate is embedded in diammonium phosphate product, keep constant product quality, reduce phosphor resource consumption, improve product nitrogen content, reduce production costs.Ammonium sulfate (NH4)
2sO
4nitrogen content is 21%, is added on the composition that can change diammonium phosphate product in diammonium phosphate product, improves product total nitrogen content.
Realize the present invention and comprise following step:
(1) by the ammonium sulfate slurry from phosphogypsum combinations body ammonium sulfate device, by shurry pump, be delivered to the ammonium sulfate slurry buffering storage tank of diammonium phosphate device, line of pipes adopts and is connected with low-pressure steam scavenging line, there are steam tracing and thermal insulation layer thereof simultaneously, prevent that ammonium sulfate slurry is at course of conveying crystallisation by cooling, blocking pipeline;
(2) keep the slip deposit liquid level of ammonium sulfate slurry buffering storage tank more than 60%, keep ammonium sulfate slurry temperature between 65～80 ℃, slip can crystallization and freezing, good fluidity;
(3), when nutrients of diammonium phosphate product is higher or when nutrients ratio is unbalance, the ammonium sulfate slurry that is stored in ammonium sulfate slurry storage tank is delivered to tubular reactor complex acid groove or washings receiving tank by toothed gear pump;
(4) ammonia scrubber interpolation strong phosphoric acid is directly washed tail gas generated by granulation, and degree of neutralization (N/P) controls≤0.65, keeps ammonia scrubber washings density 1.35～1.55g/cm
3; The washings that contains ammonium sulfate slurry is shunted by ammonia stripping circulating-pump outlet, a part is for carrying out circulation cleaning to ammonia scrubber, one enters the anti-complex acid groove preparation of pipe acid for tubular reactor, simultaneously, at pipe, add 45%～48% strong phosphoric acid in anti-complex acid groove, manage the agitator reinforcing mass transfer effect of anti-complex acid groove, the anti-complex acid of holding tube evenly, manage anti-complex acid density p=1.50～1.58g/cm
3, degree of neutralization N/P=0.35～0.60;
(5) the anti-complex acid of pipe that contains ammonium sulfate slurry is transported to 1# by managing anti-feeding pump, 2# tubular reactor, with vertical, cut and mix at tubular reactor mixing head with the high-pressure liquid ammonia (P=1.00～1.50MPa) from ammonia tank field, there is rapidly neutralization reaction, very exothermic, production High Temperature High Pressure (P=0.2～0.6MPa, T=120～150 ℃) phosphor ammonium slurry is at tubular reactor mixing head, the residence time 2～4s in slip distribution pipe, the slip of two tubular reactors is injected in drum ammonization and granulation tablets press, mix with the dried material from revert system, in tablets press, pass through coating, cohere, from modes such as granulating, form particle, and the degree of neutralization (N/P) that adds secondary benefit ammonia maintenance granulation material reaches 1.75～1.90.Granulation material is through dry, screening, cooling and external parcel, and moisture drops to below 2.5%, and the particle that extraction particle diameter is 2～4mm is delivered to warehouse as product and stores.
In above-mentioned steps (1), described ammonium sulfate slurry density 1.24～1.28g/cm
3, water ratio 40%～50%(butt), there is good water-soluble and mobility.
In above-mentioned steps (2), described ammonium sulfate slurry buffering storage tank is provided with agitator and steam heating attemperator, and skin has thermal insulation separation thermosphere.
In above-mentioned steps (3), in order to maintain concentration and the density of pipe sour regurgitation groove, the thermal equilibrium of stabilizing control system, an ammonium sulfate slurry seldom part (≤30%) directly makes an addition to the anti-complex acid groove of pipe; All the other overwhelming majority (>=70%) or all make an addition to washings receiving tank; the washings that refluxes with from washing towers such as granulation, dry, cooling, dedustings and collect mixes; by washings topping-up pump, enter the anti-complex acid groove of pipe again; by the anti-feeding pump of pipe, be delivered to tubular reactor ammoniation and granulation, form diammonium phosphate particle.
The flow of described slip, by volumetric flow meter and variable valve metering and control, adds flow along with system throughput changes and changes.Suppose to adopt ammonium sulfate (butt) content 45% ammonium sulfate slurry regulating nutrients of diammonium phosphate product, ammonium sulfate slurry density is 1250kg/m
3, making an addition to output is 60t/h features of DAP production system, by total nutrient, is 65.00% to be adjusted to 64.00%, needs to add V m
3, V=2.5 m
3/ h
V＝2.5?m
3/h
Described ammonium sulfate slurry is added the mode of taking add intermittence, and according to the result of product nutrient process analysis, dynamic adjustments is added flow.
Method of the present invention adopts ammonium sulfate slurry as filler, regulate ammonium phosphate product nutrient, reaction conditions is gentle, can effectively diammonium phosphate product total nutrient be controlled between 64.00%～64.50%, product total nutrient is stable, and is that 46-18-0 ratio distributes in the content of nitrogen, phosphorus, potassium, at product, meet under GB10205-2009 Traditional Method premium grads standard prerequisite, saved resource and cost, realization is carried nitrogen and is fallen phosphorus, promotes product Nutrient distribution balance.
This programme has the following advantages: (1) can effectively promote diammonium phosphate product to fall phosphorus to carry nitrogen and nutrient nutrient balance thereof and distribute, keep constant product quality, and regulates in nutrient process and can not rise and fall sharply and quickly; (2) ammonium sulfate slurry used is produced by phosphogypsum monoammonium phosphate device processed, consumes in a large number phosphogypsum and can save phosphogypsum cost of disposal, reduces environmental protection pressure, extends phosphogypsum slag field work-ing life; (3) by ammonium sulfate slurry and crystal, substitute the vitriol oil, stability of flow in adding procedure, reaction conditions is gentle, safe and reliable; (4) in product, containing solubility element sulphur, is one of essential element of plant production, can effectively promote comprehensive growth of farm crop.(5) keeping, on quality product basis up to standard, saving phosphoric acid resource consumption.
Accompanying drawing explanation
Fig. 1 is process flow diagram of the present invention.
Wherein: 1-ammonium sulfate slurry storage tank; 2-toothed gear pump; 3-manages anti-complex acid groove; 4-manages anti-feeding pump; 5-washings receiving tank; 6-washings topping-up pump; 7-ammonia stripping sealing groove; 8-ammonia stripping recycle pump.
Embodiment
From the ammonium sulfate slurry of phosphogypsum combinations body ammonium sulfate device, density 1.24～1.28g/cm
3, water ratio 40%～50%(butt), there is good water-soluble and mobility.By shurry pump, be delivered to diammonium phosphate device ammonium sulfate slurry buffering storage tank, line of pipes adopts and is connected with low-pressure steam scavenging line, has steam tracing and thermal insulation layer thereof simultaneously, prevents that ammonium sulfate slurry is at course of conveying crystallisation by cooling, blocking pipeline.
Ammonium sulfate slurry from ammonium sulfate device is delivered to diammonium phosphate device ammonium sulfate slurry buffering storage tank by hot insulated line, the ammonium sulfate buffering storage tank volume 60m of employing
3, keep slip deposit liquid level more than 60%.Be provided with agitator and steam heating attemperator, skin has thermal insulation separation thermosphere, keeps ammonium sulfate slurry temperature between 65～80 ℃, and slip can crystallization and freezing, good fluidity.
When nutrients of diammonium phosphate product is higher, the ammonium sulfate slurry that is stored in ammonium sulfate slurry storage tank is delivered to tubular reactor complex acid groove or washings receiving tank by toothed gear pump, in order to maintain concentration and the density of pipe sour regurgitation groove, the thermal equilibrium of stabilizing control system, an ammonium sulfate slurry seldom part (≤30%) directly makes an addition to the anti-complex acid groove of pipe; All the other overwhelming majority (>=70%) or all make an addition to washings receiving tank; the washings that refluxes with from washing towers such as granulation, dry, cooling, dedustings and collect mixes; by washings topping-up pump, enter tablets press ammonia scrubber sealing groove again, fully mix with the phegma from ammonia scrubber.
Ammonia scrubber adds strong phosphoric acid and directly washs tail gas generated by granulation, and degree of neutralization (N/P) controls≤0.65, keeps ammonia scrubber washings density 1.35～1.55g/cm
3.The washings that contains ammonium sulfate slurry is shunted by ammonia stripping circulating-pump outlet, a part (≤30%) is for carrying out circulation cleaning to ammonia scrubber, a part (>=70%) enters the anti-complex acid groove preparation of pipe acid for tubular reactor, simultaneously, at pipe, add 45%～48% strong phosphoric acid in anti-complex acid groove, manage the agitator reinforcing mass transfer effect of anti-complex acid groove, the anti-complex acid of holding tube evenly, manage anti-complex acid density p=1.50～1.58g/cm
3, degree of neutralization N/P=0.35～0.60.
The anti-complex acid of pipe that contains ammonium sulfate slurry is transported to 1# by managing anti-feeding pump, 2# tubular reactor, with vertical, cut and mix at tubular reactor mixing head with the high-pressure liquid ammonia (P=1.00～1.50MPa) from ammonia tank field, there is rapidly neutralization reaction, very exothermic, production High Temperature High Pressure (P=0.2～0.6MPa, T=120～150 ℃) phosphor ammonium slurry is at tubular reactor mixing head, the residence time 2～4s in slip distribution pipe, the slip of two tubular reactors is injected in drum ammonization and granulation tablets press, mix with the dried material from revert system, in tablets press, pass through coating, cohere, from modes such as granulating, form particle, and the degree of neutralization (N/P) that adds secondary benefit ammonia maintenance granulation material reaches 1.75～1.90.Granulation material is through dry, screening, cooling and external parcel, and moisture drops to below 2.5%, and the particle that extraction particle diameter is 2～4mm is delivered to warehouse as product and stores.
Ammonium sulfate nitrogen content 21.21%, adopts ammonium sulfate (butt) content 45% ammonium sulfate slurry regulating nutrients of diammonium phosphate product, and ammonium sulfate slurry density is 1250kg/m
3, making an addition to output is 60t/h features of DAP production system, by total nutrient, is 65.00% to be adjusted to 64.00%, needs to add V m
3, V=2.5 m
3/ h.
V＝2.5?m
3/h
Ammonium sulfate slurry is added the mode of taking add intermittence, and according to the result of product nutrient process analysis, dynamic adjustments is added flow.The diammonium phosphate device of Wengfu phosphate fertilizer plant 2 * 600,000 ton/year, daily consumes ammonium sulfate slurry and reaches 30m
3, product is stable is controlled in ratio between 64.0%～64.5% up to more than 85%.
Adopt ammonium sulfate slurry as filler, regulate ammonium phosphate product nutrient, reaction conditions is gentle, can effectively diammonium phosphate product total nutrient be controlled between 64.00%～64.50%, product total nutrient is stable, and in the content of nitrogen, phosphorus, potassium, be that 46-18-0 ratio distributes, at product, meet under GB10205-2009 Traditional Method premium grads standard, saved resource and cost.
Claims (6)
1. the method that nutrients of diammonium phosphate product regulates, is characterized in that comprising following step:
(1) by the ammonium sulfate slurry from phosphogypsum combinations body ammonium sulfate device, by shurry pump, be delivered to the ammonium sulfate slurry buffering storage tank of diammonium phosphate device, line of pipes adopts and is connected with the pipeline that low-pressure steam purges, there are steam tracing and thermal insulation layer thereof simultaneously, prevent that ammonium sulfate slurry is at course of conveying crystallisation by cooling, blocking pipeline;
(2) keep the slip deposit of ammonium sulfate slurry buffering storage tank to have enough liquid levels and surge volume, keep ammonium sulfate slurry temperature between 65～80 ℃, slip can crystallization and freezing, good fluidity;
(3), when nutrients of diammonium phosphate product is higher, the ammonium sulfate slurry that is stored in ammonium sulfate slurry buffering storage tank is delivered to tubular reactor complex acid groove or washings receiving tank by toothed gear pump;
(4) ammonia scrubber interpolation strong phosphoric acid is directly washed tail gas generated by granulation, and degree of neutralization controls≤0.65, keeps ammonia scrubber washings density 1.35～1.55g/cm
3; The washings that contains ammonium sulfate slurry is shunted by ammonia stripping circulating-pump outlet, more than 70% washing lotion is for carrying out circulation cleaning to ammonia scrubber, remaining washing lotion enters the anti-complex acid groove preparation of pipe acid for tubular reactor, simultaneously, at pipe, add 45%～48% strong phosphoric acid in anti-complex acid groove, manage the agitator reinforcing mass transfer effect of anti-complex acid groove, the anti-complex acid of holding tube evenly, manage anti-complex acid density p=1.50～1.58g/cm
3, degree of neutralization N/P=0.35～0.60;
(5) the anti-complex acid of pipe that contains ammonium sulfate slurry is transported to 1# by managing anti-feeding pump, 2# tubular reactor, with vertical, cut and mix at tubular reactor mixing head with the high-pressure liquid ammonia from ammonia tank field, there is rapidly neutralization reaction, very exothermic, the phosphor ammonium slurry of production High Temperature High Pressure is at tubular reactor mixing head, the residence time 2～4s in slip distribution pipe, the slip of two tubular reactors is injected in drum ammonization and granulation tablets press, mix with the dried material from revert system, in tablets press, pass through coating, cohere, from granulating mode, form particle, and the degree of neutralization that adds secondary benefit ammonia maintenance granulation material reaches 1.75～1.90, granulation material is through dry, screening, cooling and external parcel, and moisture drops to below 2.5%, and the particle that extraction particle diameter is 2～4mm is delivered to warehouse as product and stores.
2. the method for claim 1, is characterized in that in step (1) described ammonium sulfate slurry density 1.24～1.28g/cm
3, water ratio 40%～50%, in butt, has good water-soluble and mobility.
3. the method for claim 1, is characterized in that in step (2), and described ammonium sulfate slurry buffering storage tank is provided with agitator and steam heating attemperator, and skin has thermal insulation separation thermosphere.
4. the method for claim 1, is characterized in that the flow of described slip, by volumetric flow meter and variable valve metering and control, adds flow along with system throughput changes and changes.
5. the method for claim 1, is characterized in that described ammonium sulfate slurry adds the mode of intermittently adding taked, and according to the result of product nutrient process analysis, dynamic adjustments is added flow.
6. the method for claim 1, is characterized in that the diammonium phosphate product total nutrient obtaining is controlled in 64.00%, and product total nutrient is stable, and is that 46-18-0 ratio distributes in the content of nitrogen, phosphorus, potassium.
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| CN112430147A (en) * | 2020-11-24 | 2021-03-02 | 湖北三宁化工股份有限公司 | Method for producing ammonium phosphate sulfate by using diammonium phosphate device by using ammonia-acid method |
| CN116692920A (en) * | 2023-07-21 | 2023-09-05 | 昆明川金诺化工股份有限公司 | Production method and production system of low free water dihydrate phosphogypsum |
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| CN1070157C (en) * | 1997-09-23 | 2001-08-29 | 张智新 | Producing ammonium phosphate from ammonium carbonate |
| JP4279477B2 (en) * | 2001-04-17 | 2009-06-17 | 住友化学株式会社 | Granular fertilizer composition and method for producing the same |
| CN101973790B (en) * | 2010-10-26 | 2013-05-22 | 瓮福（集团）有限责任公司 | Method for producing granular diammonium phosphate with low concentration of nutrients by tailings |
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Address after: 550500 Guizhou Province, Qiannan Buyei and Miao Autonomous Prefecture Fuquan Racecourse town Yingbin Road No. 1 Wengfu group Patentee after: WENGFU GROUP Co.,Ltd. Address before: 23, 550002 floor, International Building, No. 57, South City Road, Nanming District, Guiyang, Guizhou Patentee before: WENGFU GROUP Co.,Ltd. |